大腸俞 Dachangshu
“Large Intestine Transport” · BL25
Foot Taiyang · 25 of 67 · back-shu of the large intestine
Where. On the line joining the tops of the hip bones (below the fourth lumbar bump), two finger-widths from the spine.
For. Constipation or loose stools; low back and leg pain.
Press. Hands on hips, press with the thumbs, fairly firm, about a minute.
大腸俞，在第十六椎下，兩傍各一寸五分按 · Press with me
Six slow breaths
About a minute. Press as you breathe out, ease as you breathe in.
鄰 · Neighbouring leaves
Where Dachangshu Sits on the Low Back
Dachangshu takes its place in the low back, in the short, sturdy stretch of spine that carries the standing load between rib cage and pelvis. The dataset locates it precisely: on the lower back, below the spinous process of the fourth lumbar vertebra — level with the highest points of the iliac crests — 1.5 cun lateral to the posterior midline. Unpacked for hands rather than rulers: the five lumbar vertebrae wear broad, blunt, boxy ridges compared with the finer knobs higher up, and a soft step waits beneath the fourth of them. The iliac crests are the wings of the hip bones felt when hands rest on the waist, and the line joining their highest points crosses the spine in the neighbourhood of that very fourth lumbar gap. From the centre seam, step outward one and a half cun — mirrored on both sides — and there sits Dachangshu.
A cun is the traditional measuring unit of Chinese point-location: proportional lengths taken from the person being examined rather than from a ruler, so a cun at the waist of a broad-framed adult differs from a cun on a slight teenager. One practical rendering passed along through self-location teaching holds that the width of the index and middle fingers pressed together comes close to one and a half cun on many adult hands — helpful arithmetic, worth trusting only alongside the bony landmarks. Beneath the skin the ground is among the friendliest on the whole torso: the spot rests on the thick muscles flanking the lumbar spine, generously padded on most bodies, with the deeper structures of the trunk lying far beyond anything gentle fingertip contact could ever reach. Why discipline still matters at this easy-going station is a matter the safety section takes up in full.
The neighborhood completes the map. One ridge higher, beneath the third lumbar vertebra, the same lateral line carries Qihaishu (BL24); one ridge lower, beneath the fifth, stands Guanyuanshu (BL26); two above, beneath the second lumbar vertebra and level with the navel, sits Shenshu (BL23), the kidney’s own station. Classical teaching lined these addresses up organ by organ along the inner route of the bladder meridian — the longest pathway in the body, sixty-seven stations strong — drawn in the old cartography from the inner corner of the eye, sweeping over the head, and descending the whole back to the little toe. Down the spine it travels in paired vertical routes, the inner one running 1.5 cun from the midline — the road Dachangshu stands on — and along that inner road the tradition arranged the transports of the organs like offices along a corridor, the bowel keeping its window at the fourth lumbar storey.
A Self-Palpation Walkthrough
Stand relaxed, feet a comfortable width apart, or sit upright on a firm chair with shoulders heavy — slumping blurs the very edges about to be read. Rest the backs of your hands on your waist and walk the fingertips inward along the upper rim of each hip bone until the highest point of the crest announces itself beneath the pad. Imagine a belt drawn through those two highest points straight around the body: where it crosses the spine at the back is the neighbourhood of the gap beneath the fourth lumbar ridge. If the bony landmarks feel shy, bow gently forward and let the lumbar ridges stand proud, then settle the pad of a finger in the soft step below the fourth. From there slide outward across the muscle until you have crossed roughly the width of two pressed-together fingers, and rest where the flesh forms a gentle cord-like column flanking the spine. That shallow resting place, on either side of the seam, is the address. Repeat the whole search on the other side.
Confirmations cost nothing. Touch feather-light and compare sides: many people register a faint, dull awareness at the genuine spot and little sensation a thumb-width away. Take a slow breath and notice how little this stretch of back stirs compared with the chest — that stillness quietly confirms the search stayed on the back’s quiet side. Check the horizontal position too: the true spot hugs the spine’s side of the low back, on the muscle column, not out toward the softer curve of the waist. And lean on the neighbors as witnesses: whoever has found Guanyuanshu one ridge below, or Qihaishu one ridge above, can trust Dachangshu to sit exactly between them; anyone who knows Shenshu level with the navel can count down two ridges to arrive here. If bare bone meets the fingertip, the search has wandered onto the spine itself; ease back toward the muscle column and begin again.
Three slips account for nearly every mislocation here. Trying to count vertebrae all the way down from the neck comes first — the tally is long, the ridges change character halfway, and a wandering count lands nowhere useful; the iliac-crest route exists precisely to spare you that climb. Mistaking the crest rim itself for a spinal ridge comes second: the hip bone curves away sideways, while the vertebral ridges stack in a straight vertical seam — if your landmark walks off toward the side, you are following the pelvis, not the spine. Drifting outward past the muscle column toward the soft waist comes third; the correction never changes — return toward the seam. And remember the mirror pair: there are two Dachangshu, and neither substitutes for the other. When doubt outlives every test, resist guessing from wherever the wandering ended; go back to the hips, redraw the crest line once more, and measure out slowly from the top.
Reading the Name: Large Intestine Transport
The name is a job description in three characters. Da 大 means large — plain size vocabulary. Chang 腸 means intestine or gut, the long coiled passage classical medicine watched over with such attention. Shu 俞 belongs to the family of characters used across the point catalogue for stations of transfer, carrying the old sense of conveying or infusing, the way water passes along a channel from reach to reach. Together the name reads as the large intestine transport: the place where the bowel system delivers its activity toward the back. Classical teaching set an entire series of such addresses beside the spine, one for each of the organs, all sharing the suffix character — the lung keeps Feishu high on the back, the stomach holds Weishu, and at the fourth lumbar vertebra the office falls to the large intestine. Wherever the tradition wanted to say that an organ keeps a window on the back, it wrote shu.
The large intestine occupied a definite seat in classical physiology. Among the five phases it was assigned metal, sharing the element with its partner the lung; its working was described as receiving what the digestion passed downward, drawing off fluid from what remained, and forming and conveying the dregs onward and out — the final stretch of the long road food travels. In that frame, complaints of the bowel were read as the conveyance losing its rhythm: running too swift, or stalling on the way. Classical lists also liked pairing: each back transport had a companion gathering place on the front of the trunk called a mu point, and for the large intestine that companion is Tianshu (ST25), found on the abdomen two cun to the side of the navel’s centre — front door and back window, tradition suggested, holding one office between them. There is even a small poetry in the pair: front station and back station both carry the bowel in their charge. All of this is the heritage’s own weather map, offered warmly for understanding, not as anatomy confirmed.
Pinyin renders the name Dàchángshū: da drops on the sharp, falling fourth tone, chang rises on the lilting second tone, and shu rides high and even on the first. The hanzi trio 大腸俞 stays legible at a glance — large, intestine, transport — and like many points named for what they do rather than where they sit, the label performs real work. Gates imply watching a threshold; transports imply delivery. The name quietly states its instructions: whatever concerns the bowel’s conveying work, this is where the tradition delivered its attention on the back. A reader who remembers just the two ideas — bowel, and delivery-to-the-back — carries the whole doctrine in miniature.
Traditional Indications, Explained
The recorded indications read: abdominal distension, diarrhoea, constipation, lumbar and leg pain, sciatica, and enuresis. Abdominal distension is a distinct traditional concept: a subjective tightness, swelling, or stuck quality across the belly, understood as qi failing to move freely there. The two bowel entries travel together in the traditional telling — diarrhoea and constipation were read as two faces of one failure, the conveyance off its natural rhythm, too swift in one case and too slow in the other — and the large intestine’s own back address anchored classical discussions of both, much as a household treats its own front door: the first address consulted whenever the trouble came knocking.
Then come the entries that belong to the landscape itself. Lumbar and leg pain reads plainly once the channel map opens: the bladder meridian pours down the entire back, the inner line serving the territory it traverses, and this lowest stretch shares the same long columns of paraspinal muscle that ache in many backs. Sciatica — an older heading for discomfort tracking from the low back through the hip and down the back of the leg — belonged in classical discussions to points along that descending road, and this station stood where back becomes pelvis. Enuresis, bedwetting, looks the furthest afield until the traditional reasoning is recalled: classical teaching kept the low back as the home region of the kidney system, whose wide duties included the water passages, so lists sometimes gathered bedwetting at these lower stations. It is a traditional association, recorded faithfully and offered for understanding — not a promise attached to pressing.
It bears repeating plainly: these are the traditional uses recorded in a licensed dataset and classical literature, presented for cultural and historical understanding, not claims that pressing this point treats disease. Constipation and bowel changes especially deserve that honesty — they have many possible reasons, and persistent change calls for assessment rather than patience with a pressure routine. Where modern research touches self-applied pressure at all, reviews suggest effects are modest and context-dependent, and evidence specific to any single point remains thin. Hold the tradition lightly, and hold the safety rules firmly.
Self-Care Acupressure at Home
Once located, settle into position: seated on a firm chair, spine tall but unforced, shoulders heavy — or lying comfortably with knees softened over a cushion, which lets the low back widen and the search grow easier. Reach the opposite hand behind the waist and rest the curled fingers so the pads — never the tips — meet the muscle column found earlier. Begin with contact alone for a few slow breaths, then add small, unhurried circles, letting the skin glide over the tissue beneath rather than grinding against it. Pressure should register as pleasant dullness or mild warmth, never sharpness. A common home rhythm is one to three minutes per side, once or twice daily, each circle riding a long exhale out; then swap hands and match the other side, keeping the two sessions symmetrical.
Quality outranks duration, as it does everywhere in gentle practice. Light, patient, regularly repeated contact is the whole discipline; jabbing teaches the body nothing and startles a stretch of back that spends its days braced against chairs. Warm cold hands first, because chilled muscle guards. Choose a quiet corner over a screen and let the session double as a pause — the low back rarely receives deliberate attention, and simply being attended to settles many people. Readers who keep routines anchor this one somewhere natural: after the morning shower, before lights-out, or during the afternoon lull. Consistency, not intensity, is what self-care traditions actually ask for, here as everywhere.
Treat the exercise as a few minutes of attention paid to a stretch of yourself that cannot see itself. Across weeks you may notice the area feels less guarded, breathing feels easier while you press, or simply that you spent ninety seconds tending your own back — all outcomes fit the honest scope of self-acupressure. What does not fit is escalation: pressing harder, longer, or deeper to force a result. Curiosity pulling that way should meet the same answer every time — return to gentleness, or stop for the day. The point is not going anywhere; tomorrow it will wait at the same fourth-lumbar address, level with the hips as always.
Cautions and Safe Practice
The licensed record attaches no specific caution to this entry — a quiet contrast with points high on the chest or throat, and a reflection of geography: the well-padded muscles of the low back keep the structures that matter farther from gentle fingertip reach than almost anywhere else on the trunk. Absence of a caution is not an invitation for force; it simply means this station asks no special fear, only the ordinary discipline that governs every session of surface self-care everywhere on the body. Feather-light fingertip work engages skin and superficial muscle alone, and honouring that boundary is the whole of the technique.
For fingertip practice the rules follow plainly. Keep contact light and strictly superficial — the intention stays in skin and superficial muscle, never driving inward toward the spine. Use finger pads, never elbows, knuckles, tools, or devices. Skip the point entirely during feverish illness or any acute flare, and over broken, irritated, or inflamed skin, including sprays, patches, or dressings already applied to the area. After recent back injury, injection, or surgery, wait until a clinician clears ordinary activity. Sharp, electric, or radiating sensation — especially anything streaking down either leg — means stop at once, and not again that day. Pregnant readers, and anyone living with ongoing digestive, kidney, or spinal conditions, should consult a qualified practitioner before adding any new point practice. And when energy runs low or unwellness visits, the wisest session is the postponed one — rest is also self-care.
Over everything stands the wider rule: this page is educational, and acupressure is self-care, not diagnosis or therapy. Seek prompt medical care — not a longer pressing session — for blood in the stool, bowel habits that change persistently without clear cause, numbness or weakness spreading into either leg, new back pain joined by loss of control of bladder or bowel, which is urgent, or back pain that worsens steadily despite rest. Persistent complaints belong with a licensed practitioner, medical or East Asian medical as suits the problem. The image of the bowel’s window on the back is elegant, and it earns its keep as memory and meaning; but the safest gift Dachangshu offers most people is a calmer acquaintance with their own low back, tended lightly and surrendered promptly whenever the body asks for more than gentleness can give.
Dachangshu, the Large Intestine Transport, stands low on the back beside the spine, level with the top rims of the hip bones. Classical teaching made it the large intestine’s own address on the back, the station reached for when bowels stalled or ran unsettled. This guide walks through finding it by touch and pressing it gently.
Self-care limits
Frequently asked
- How do I find Dachangshu without knowing anything about cun?
- Use the hips as the whole map. Rest your hands on your waist, trace each hip bone upward to its highest rim, and picture a belt drawn through both rims straight around the body — it meets the spine near the gap beneath the fourth lumbar ridge. Settle a finger in that soft step, then slide sideways about the width of two pressed-together fingers onto the muscle column beside the spine. Guanyuanshu waits one ridge below and Qihaishu one above, and the trio confirm one another. Cun measurements encode the same landmark sequence in proportional language.
- Is pressing Dachangshu myself actually safe?
- Gentle fingertip pressure held on the surface is generally reasonable self-care for healthy adults — the licensed record notes no special caution for this entry, and the well-padded low back keeps sensitive structures beyond the reach of surface contact. That is permission for lightness, not force. Respect the stop signals all the same: sharp pain, any sensation radiating down a leg, or discomfort that worsens means finish immediately, and fever, acute illness, or irritated skin cancels the session entirely.
- What did classical practice use Dachangshu for?
- The traditional record lists abdominal distension, diarrhoea, constipation, lumbar and leg pain, sciatica, and enuresis. The name tells the headline: as the large intestine’s own transport point on the back, Dachangshu anchored classical discussions of the bowel’s conveying work. Those are traditional frameworks for understanding the body, documented for context — not evidence-backed treatment claims.
- Why is a point for the bowel located on the back?
- Classical cartography draws the bladder meridian descending the back along two paired routes, and the inner line — 1.5 cun from the midline — carries a procession of stations the tradition matched organ by organ, the large intestine keeping its window at the fourth lumbar vertebra. Each back transport also had a front companion, the mu gathering place — for the large intestine, Tianshu (ST25) beside the navel — and tradition often read the pair as front door and back window holding one office between them. Bilateral symmetry doubles everything: there is a Dachangshu on each side of the spine.
- Can acupressure at Dachangshu replace seeing a doctor about bowel changes?
- No. Self-acupressure is a comfort practice, not a diagnostic tool. Blood in the stool, bowel habits that shift and stay shifted, leg numbness or weakness, or back pain with loss of bladder or bowel control call for professional assessment promptly — some urgently. Think of daily self-care and clinical medicine as caretakers of two different doors, each minding its own threshold, neither substituting for the other.
Sources
- 01WHO Standard Acupuncture Point Locations in the Western Pacific Region (2008), World Health Organization — nomenclature conventions.
- 02A Manual of Acupuncture, Peter Deadman, Mazin Al-Khafaji and Kevin Baker — point-name tradition, back-shu theory, and bladder-channel context.
- 03aijiu-mpvue (MIT License) licensed dataset, entry for BL25 Dachangshu — location, point class, actions, and caution record.
Last reviewed
牌記This leaf, for machines
Old books ended with a colophon saying who printed them. Every leaf here carries the same facts as structured data for agents and search, with no layout in the way.
- GET /en/points/bl25/leaf.json
- GET /zh-hant/points/bl25/leaf.json
- GET /zh-cn/points/bl25/leaf.json
- /llms.txt — the index of every leaf
- JSON-LD in the page: MedicalWebPage, MedicalEntity and FAQPage
{
"id": "BL25",
"name": {
"en": "Dachangshu",
"gloss": "Large Intestine Transport",
"zh-Hant": "大腸俞",
"zh-Hans": "大肠俞"
},
"channel": {
"id": "BL",
"order": 25,
"of": 67
},
"location": {
"text": "On the line joining the tops of the hip bones (below the fourth lumbar bump), two finger-widths from the spine."
},
"for": [
"constipation or loose stools",
"low back and leg pain"
],
"press": {
"text": "Hands on hips, press with the thumbs, fairly firm, about a minute.",
"seconds": 60
},
"cautions": [],
"source": "Zhenjiu Jiayi Jing, book 3",
"url": "https://acupoints.com/en/points/bl25",
"lastReviewed": "2026-08-24"
}